Wood bending machinery



y 1951 K. MICHAELIS 2,551,333

WOOD BENDING MACHINERY Filed Nov. 2, 1944 IN V EN TOR.

my at Patented May 1, 1951 UNITED STTES Zi- ATENT OFFICE,

WOOD BENDING MACHINERY Karl Michaelis, New York, N. Y.

. Application November 2, 1944, Serial No. 561,584

2 Claims.

This invention relates to machines for bending wood and moreparticularly wood panels and boards, to difierent radii as desired ineach individual case.

In existing wood bending machines bending forms or tools of variousradii are required to be mounted in the machine according to the radiusdesired in each individual case.

In contradistinction to this, devices constructed in accordance with thepresent invention are fitted with supports, checks or the like which canbe adjusted to diiferent relative positions in such manner as to enablewood panels or boards or the like placed thereon or therebetween, andwhich have been rendered pliable by the action of dry heat, to be bentto any of the many radii for which these supports or checks can be setin the machine. Obviously the provision of such adjustable shapingmembers renders it easy to change over from one radius to the other andtends to lower the price of the machines.

In the drawings afiixed to this specification and forming part thereofan embodiment of this invention is illustrated diagrammatically by wayof example.

In the drawings Figs. 1 and 2 are a front view and a cross-section onthe line 11-11 in Fig. 1, respectively, of a machine for bending longboards or panels to arch form.

In the machine illustrated in Figs. 1 and 2, 80 is a vertical wall,represented here by a metal plate, which is formed with a number ofparallel vertical slits 8 I. In these slits are fitted for verticaladjustment brackets 82 carrying rounded heads 83. Threaded pins 84extending from the backs of the brackets and carrying nuts serve forfixing each bracket in its slit in the position allotted to it.

85 is a steel plate horizontally arranged on top and to the rear of thewall 80. 86 indicates electrical heating elements arranged underneaththe plate 85. 8'! are boards which, before being bent, are renderedpliable by the action of the heat accumulating in the steel plate 85.This plate thus functions as a preheating plate such as described in myU. S. Patent No. 2,189,078. 88 is a flexible steel strip of a Widthequalling or exceeding the length of the bracket heads 93. This strip isheated, for instance, by means of electrical heating elements 95 mountedon its bottom surface.

89 are boards which, after having been preheated on the table 85, weremoved into position on top of the steel strip 88 and bent, together withthis strip, to the curvature defined by the position of the totality ofbrackets adjusted in 2 their slits with their head arranged along thedesired curve.

The force required to bend the pliable boards may for instance bederived from a motor winch 9|, the drum 90 of which projects underneaththe table and the brackets. Cables or chains 96 slipped over pins 94fixed in the ends of the boards and running over sheaves 9'! are woundon the drum when the motor is started, and pull the boards down onto thebrackets.

I wish it to be understood that I do not desire to be limited to thedetails shown and described, for obvious modifications will occur to aperson skilled in the art.

I claim:

1. In a Wood bending machine, relatively fixed means arranged on an arehaving a convex configuration and constituting a former, a normallyplanar flexible heat conductive element having heating means aifixedthereto, having one face in tangential line contact with said former soas to form a support for a wood blank on its other face and means forexerting a bending force at each end of said blank to move said ends andthe underlying corresponding portions of said heater element around saidformer with the flexible heater interposed between the blank and theformer.

2. The wood bending machine of claim 1 wherein the relatively fixedmeans comprises a plurality of adjustably supported checks arrangedalong said arc.

KARL MICHAELIS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 33,395 Luckhaupt Oct. 1, 186151,826 Griffiths Jan. 2, 1866 106,880 Solomon Aug. 30, 1870 337,113Bailey Mar. 2, 1886 541,890 Stickley July 2, 1895 1,434,651 ElmendorfNov. 7, 1922 1,465,215 Hall Aug. 14, 1923 1,561,613 McKeown Nov. 17,1925 1,766,963 Strupe June 24, 1930 1,816,377 Hobracht July 28, 19312,189,078 Michaelis 1- Feb. 6, 1940 2,189,150 Owens Feb. 6, 1940 FOREIGNPATENTS Number Country Date 187,977 Great Britain Sept. 14, 1907

